help identifying a part

[gtangas]

hey guys

a friend of mine gave me an amazing surprise! An old davoli amp from 1973
its a 200wts tube amp.... and hehhe its partial working!

it uses 4xEL504 a EL80 and a ECC84
2 channels, a small reverb tank, tremolo and gain... its a beauty!!

some pics of one that i found on the web (the amp part)





this a similar one

I already found problems on some caps (filtering) and a few more things to change....

so i found the schematic of the effects/Eq/etc and i cant identify a component

its a box shape with some comps inside (resistors, caps)  and covered with some type of resin

from the schematic can anyone tell what those are?

this a photo not of my unit but it shows the parts....